| With economic development, wastewater from industry and agriculture increases greatly. There are many kinds of suspended substance in wastewater. These suspended particles are discharged into rivers and lakes together with wastewater, and pollute lots of water sources. Besides this, SS has a negative influence on a system of wastewater treatment, which leads to criticalnon-conformity of treated water or equipment malfunction.In researches of ballast water treatment, the main methods for SS separation include hydrocyclone, flotation, filtration and etc.. Candidates for solid-liquid separation in ballast water treatment should be not only effective but also reliable. In preliminary works, all kinds of solid-liquid separation methods were analyzed in detailed, and filtration was adopted finally. An experimental system of simulated ballast water treatment was established in the lab. In the system, micro-pore ceramic filter (MPCF) with wall-flow structure was taken as a primary method for filtration. Comparing with other filter, MPCF has the advantages of smaller space, larger effective filtering area, corrosion resisting and etc., which is suitable for ballast water treatment.In preliminary experiments, because the concentration of TSS (Total Suspended Solids) in native seawater was less than 50mg/L which is required in G8(Guidelines for approval of ballast water management system), SS were added into native seawater to simulate the tested water. Calcium-based organic bentonite with the size of 200 meshes was selected as the simulated SS. In bench-scale experiment, with the filter of the effective volume 6L, the dosage of additive SS is 110mg in per 1L seawater, and the optimal flow rate is 5m3/h. In medium-scale experiment, with the filter of the effective volume 20L, the dosage of additive SS is 70mg, and the optimal flow rate is 16m3/h.In this thesis, the main work is to investigate the stability and effectiveness of the MPCF, discuss the relationships between pressure loss and volume of treated water, and analyze the life span of the filter. Sample the seawater before the treatment, before the filtration and after the filtration during experiments respectively, test the concentration of SS, determine the effectiveness of the filter, and obtain the effect of SS on the filter as well. In the experiments, both bench-scale test and medium-scale test show that the pressure loss increases with the accumulated volume of seawater, and the greater the treated flow rate, the higher the pressure loss be. In bench-scale experiment, the flow rate is 2.5m3/h, the threshold value of the pressure loss is 0.58MPa, the accumulated volume of treated seawater is 5.4m3, and the average removal rate of TSS is 58%. In medium-scale experiment, the flow rate is 16m3/h, the threshold value of the pressure loss is 0.2MPa, the accumulated volume of treated seawater reaches 85m3 after 5.3h continuous running, the average removal rate of the primary screen filter on TSS is 30%, and the MPCF removes the rested SS with the removal rates of 12%.The water backwashing is utilized for the regeneration of the MPCF, and 96% pressure loss of both in bench-scale test and in medium-scale test is recovered with less than 1m3 water. In order to study the simulated SS in detailed, a scanning electron microscopy (SEM) is used in the test. Analyzing the size and the shape of the SS before and after the filtration and counting the particles with different diameter, the results show that the simulated SS is irregular shape, the SS with the diameter of less than 20μm account for 70%. The MPCF has an obvious effect on removing SS with the diameter of less than 75μm, and removes SS with the diameter of greater than 100μm efficiently.
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